P3D Re: RBT mounts

["Dr. George A. Themelis" <DrT-3d@xxxxxxxxxxxxxxxxxxxxxxxxxxx>]

I mount my slides with the white face in front.  Many people find
the black in front to work better for viewers.  If the projector
is in good shape (good heat absorbing filters) then the black in
front would not be a problem and there are people known to have the
black always in front.  But because my slides go through many 
different projectors, I want to be in the safe side so I keep the
white in front.

I have also treated the line (also an arrow) as the top.  I think
I have heard that this might make a difference in an RBT projector
but for viewers or any other projector the mounts are symmetric and
the up to down orientation does not make a difference.  The 4p 
(Nimslo) mounts are asymmetric and they normally crop the image
more at the top (to block the exposure light indication from the
Nimslo camera).  But, if you want to crop the bottom in purpose
(in non-Nimlso slides) then you can use it upside down and you
can also switch orientations in the black and white parts to
crop *both* top and bottoms.

I use markers to write on the mounts (white = front face).  I even
use a red marker for the "thumb mark" instead of a sticker.
Sometimes I put an adhesive label in the back (black) with my
name but lately I have been writing this with a marker of 
different color in the front.

George Themelis